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1.
Molecules ; 29(13)2024 Jun 23.
Artículo en Inglés | MEDLINE | ID: mdl-38998936

RESUMEN

Metabolic alterations are increasingly recognized as important aspects of colorectal cancer (CRC), offering potential avenues for identifying therapeutic targets. Previous studies have demonstrated the cytotoxic potential of bamboo leaf extract obtained from Guadua incana (BLEGI) against HCT-116 colon cancer cells. However, the altered metabolic pathways in these tumor cells remain unknown. Therefore, this study aimed to employ an untargeted metabolomic approach to reveal the metabolic alterations of the endometabolome and exometabolome of HCT-116 cells upon exposure to BLEGI treatment. First, a chemical characterization of the BLEGI was conducted through liquid chromatography coupled with mass spectrometry (LC-MS). Next, we assessed cell viability via MTT and morphological analysis using an immunofluorescence assay against colon cancer cells, and anti-inflammatory activity using an LPS-stimulated macrophage model. Subsequently, we employed LC-MS and proton nuclear magnetic resonance (1H-NMR) to investigate intra- and extracellular changes. Chemical characterization primarily revealed the presence of compounds with a flavone glycoside scaffold. Immunofluorescence analysis showed condensed chromatin and subsequent formation of apoptotic bodies, suggesting cell death by apoptosis. The results of the metabolomic analysis showed 98 differential metabolites, involved in glutathione, tricarboxylic acid cycle, and lipoic acid metabolism, among others. Additionally, BLEGI demonstrated significant nitric oxide (NO) inhibitory capacity in macrophage cells. This study enhances our understanding of BLEGI's possible mechanism of action and provides fresh insights into therapeutic targets for treating this disease.


Asunto(s)
Neoplasias del Colon , Extractos Vegetales , Hojas de la Planta , Humanos , Extractos Vegetales/farmacología , Extractos Vegetales/química , Hojas de la Planta/química , Neoplasias del Colon/tratamiento farmacológico , Neoplasias del Colon/metabolismo , Neoplasias del Colon/patología , Células HCT116 , Metabolómica/métodos , Metaboloma/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Apoptosis/efectos de los fármacos , Animales , Células RAW 264.7 , Ratones , Cromatografía Liquida
2.
Fitoterapia ; 177: 106101, 2024 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-38945495

RESUMEN

Helicobacter pylori is a bacterium that is present in the stomach of about 50% of the global population and is associated with several gastric disorders, including cancer. Natural products with antimicrobial activity have been tested against H. pylori, among them Trichilia catigua (catuaba), which is widely distributed in Brazil. This study aimed to evaluate extracts of T. catigua bark against H. pylori via determination of the minimum inhibitory and bactericidal concentrations (MIC and MBC); evaluation of virulence factors by real-time PCR, synergism with standard antimicrobials and morphology by scanning electron microscopy and simulations of the mechanism of action by molecular docking. The ethyl acetate fraction provided the best results, with an MIC50 of 250 µg/mL and a 42.34% reduction in urease activity, along with reduced expression of the CagA and VacA genes, which encode for the main virulence factors. This fraction presented synergistic activity with clarithromycin, reducing the MIC of the drug by four-fold. Docking simulations suggested that the extracts inhibit fatty acid synthesis by the FAS-II system, causing damage to the cell membrane. Therefore, T. catigua extracts have potential as an adjuvant to treatment and are promising for the development of new anti-H. pylori drugs.

3.
Biomed Pharmacother ; 171: 116178, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38266624

RESUMEN

Type 2 diabetes mellitus (T2D) is a chronic metabolic disorder characterized by an increase in oxidative stress, which is itself related to development of T2D's main chronic complications. Oxidative stress caused by elevated production of reactive species of oxygen and decrease of antioxidant defense system level, leads to activation of lipid peroxidation (LPO) and oxidative lipoprotein modification with increasing atherogenicity. Therefore, the aim of this study was to evaluate whether pharmacotherapeutic follow-up in patients with T2D, users and non-users of insulin, interferes with the levels of oxidative stress, measuring lipid peroxidation and protein oxidation, nitric oxide and superoxide dismutase levels. After the follow-up, there was a decrease in nitric oxide levels and an increase in superoxide dismutase concentration for the group with insulin therapy. Accordingly, these results show that the proposed pharmaceutical care program reduced the oxidative stress levels, mainly in patients in insulin therapy, as a consequence, can impact in the surging of the main chronic complications in T2D.


Asunto(s)
Diabetes Mellitus Tipo 2 , Humanos , Diabetes Mellitus Tipo 2/complicaciones , Óxido Nítrico/metabolismo , Estrés Oxidativo/fisiología , Antioxidantes/metabolismo , Superóxido Dismutasa/metabolismo , Peroxidación de Lípido , Insulina/metabolismo
4.
Nat Prod Res ; : 1-5, 2023 Nov 17.
Artículo en Inglés | MEDLINE | ID: mdl-37975557

RESUMEN

Eugenia uniflora leaves are a source of flavonoids and ellagitannins, and the Brazilian population uses them to treat various diseases, including gastrointestinal disorders. This study aimed to determine if the ethanol extract and other derivatives are effective cytotoxic agents against gastric adenocarcinoma (AGS cells) and anti-H. pylori agent, its chemical composition, and mass spectrometry characterization of the more abundant compounds. The results were compared with the literature. The aqueous fraction, rich in Oenothein B and Gemin D/Hippomanin A, showed anti-H. pylori activity and higher cytotoxicity on AGS cells compared to the other samples analysed. Furthermore, the ESI(-) FT-ICR MS characterized the more abundant phenolic compounds, including Quinic Acid, Myricitrin, Gemin D/Hippomanin A, and Oenothein. Therefore, the activity of the ethanolic extract and aqueous fraction for gastric cancer and against H-pylori seems to originate from the antiproliferative and bacteriostatic effects of tannins and flavonoids.

5.
Chem Biodivers ; 20(11): e202300863, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37747297

RESUMEN

Oreochromis niloticus (Nile tilapia) skin is a by-product of Brazilian fish farming, rich in collagen. The present study aims to evaluate the wound healing, antioxidant, and antimicrobial potential of the raw hydrolyzed extract of Nile tilapia skin, as well as the identification of the main compounds. The in vitro activity was performed using antioxidant, antimicrobial and scratch wound healing assays. An in vivo experiment was performed to evaluate the wound healing potential. On days 1, 7, 14 and 21, the lesions were photographed to assess wound retraction and on the 7th , 14th and 21st  days the skins were removed for histological evaluation and the blood of the animals was collected for glutamic oxaloacetic transaminase and glutamic pyruvic transaminase determination. The chemical study was carried out through liquid chromatography-tandem mass spectrometry and de novo sequencing of peptides. The in vitro assays showed a reduction of the gap area in 24 h, dose-dependent antimicrobial activity for both bacteria, and antioxidant activity. The chemical analysis highlighted the presence of active biopeptides. The histological evaluation showed that the raw hydrolyzed extract of Nile tilapia skin has a healing potential, and does not present toxicological effects; therefore, is promising for the treatment of wounds.


Asunto(s)
Antiinfecciosos , Cíclidos , Animales , Cíclidos/microbiología , Antioxidantes/farmacología , Cromatografía de Gases y Espectrometría de Masas , Antiinfecciosos/farmacología , Cicatrización de Heridas
6.
Chem Biodivers ; 20(10): e202301066, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37646700

RESUMEN

Helicobacter pylori colonizes the gastric epithelium of 50 % of world population and it is the main etiological agent of human chronic gastritis, peptic ulcer, and gastric cancer. In this study, we synthesized and characterized a series of 14 chalcones and evaluated their anti-H. pylori, NO inhibition (in vitro and in silico), and AGS cells cytotoxic effects. Compounds 3b and 3h showed MIC of 8 µg/mL. We observed structure-activity relationships, mainly related to the influence of methoxy substituent at C-2 (3b) and the nitro group at C-4 (3h) in chalcone scaffold. The fourteen chalcones inhibited the NO production in LPS-stimulated macrophages and showed potential for interaction on the active site of the iNOS enzyme. Finally, 3b and 3h showed the highest selectivity to the AGS cell lines. Thus, ours results suggest 3b and 3h as potential candidates for design of new and effective agents against H. pylori and related diseases.

7.
Mar Drugs ; 21(6)2023 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-37367643

RESUMEN

Studies estimate that nearly 2 million new cases of gastric cancer will occur worldwide during the next two decades, which will increase mortality associated with cancer and the demand for new treatments. Marine algae of the Laurencia genus have secondary metabolites known for their cytotoxic action, such as terpenes and acetogenins. The species Laurencia obtusa has demonstrated cytotoxicity against many types of tumors in previous analyses. In this study, we determined the structure of terpenes, acetogenins, and one fatty acid of Laurencia using mass spectrometry (ESI-FT-ICR/MS). In vitro cytotoxicity assays were performed with adenocarcinoma gastric cells (AGS) to select the most cytotoxic fraction of the crude extract of L. obtusa. The Hex:AcOEt fraction was the most cytotoxic, with IC50 9.23 µg/mL. The selectivity index of 15.56 shows that the Hex:AcOEt fraction is selective to cancer cells. Compounds obtained from L. obtusa were tested by the analysis of crystallographic complexes. Molecular docking calculations on the active site of the HIF-2α protein showed the highest affinity for sesquiterpene chermesiterpenoid B, identified from HEX:AcOEt fraction, reaching a score of 65.9. The results indicate that L. obtusa presents potential compounds to be used in the treatment of neoplasms, such as gastric adenocarcinoma.


Asunto(s)
Antineoplásicos , Laurencia , Sesquiterpenos , Laurencia/química , Acetogeninas/química , Simulación del Acoplamiento Molecular , Terpenos/metabolismo , Sesquiterpenos/farmacología , Sesquiterpenos/química , Antineoplásicos/farmacología , Antineoplásicos/metabolismo
8.
Nat Prod Res ; 37(24): 4267-4273, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36788415

RESUMEN

Ethanol extract from the aerial parts of Euphorbia tirucalli L. as well as the latex of the plant suspended in water are used by the Brazilian population for the treatment of various diseases, including cancer. The purposes of this study were to determine if the ethanol extract is effective as cytotoxic agent against gastric adenocarcinoma cells (AGS) and its chemical composition by GC-MS, ESI-(-)-FT-ICR MS and (-)-ESI-LTQ-MS/MS. The results were compared with that of latex previously described by us. Hexane and aqueous fractions showed higher cytotoxicity on AGS cells. Nine triterpene compounds were detected by GC-MS in hexane fraction, including euphol and friedelin, while ellagic acid was identified as main phenolic compound in aqueous extract. Therefore, the greater cytotoxic activity of the ethanol extract of the aerial parts of Euphorbia tirucalli for gastric cancer, when compared to latex, seems to originate from the antiproliferative effects of ellagic acid and triterpenes.


Asunto(s)
Adenocarcinoma , Antineoplásicos , Euphorbia , Neoplasias Gástricas , Triterpenos , Humanos , Euphorbia/química , Látex/química , Hexanos , Espectrometría de Masas en Tándem , Neoplasias Gástricas/tratamiento farmacológico , Ácido Elágico , Extractos Vegetales/farmacología , Triterpenos/farmacología , Adenocarcinoma/tratamiento farmacológico , Componentes Aéreos de las Plantas , Etanol
9.
J Biomol Struct Dyn ; 41(9): 3835-3846, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-35356863

RESUMEN

Herein we describe the use of molecular docking simulations, quantitative structure-activity relationships studies and ADMETox predictions to analyse the molecular recognition of a series of 7-aryl-2,4-diaminoquinazoline derivatives on the inhibition of Staphylococcus aureus dihydrofolate reductase and conducted a virtual screening to discover new potential inhibitors. A quantitative structure-activity relationship model was developed using 40 compounds and two selected descriptors. These descriptors indicated the importance of pKa and molar refractivity for the inhibitory activity against SaDHFR. The values of R2train, CVLOO and R2test generated by the model were 0.808, 0.766, and 0.785, respectively. The integration between QSAR, molecular docking, ADMETox analysis and molecular dynamics simulations with binding free energies calculation, yielded the compounds PC-124127620, PC-124127795 and PC-124127805 as promising candidates to SaDHFR inhibitors. These compounds presented high potency, good pharmacokinetics and toxicological profile. Thus, these molecules are good potential antimicrobial agent to treatment of infect disease caused by S. aureus.Communicated by Ramaswamy H. Sarma.


Asunto(s)
Antagonistas del Ácido Fólico , Staphylococcus aureus , Antagonistas del Ácido Fólico/farmacología , Simulación del Acoplamiento Molecular , Simulación de Dinámica Molecular , Relación Estructura-Actividad Cuantitativa , Staphylococcus aureus/química
10.
Chem Biol Drug Des ; 101(2): 350-363, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36053023

RESUMEN

The high morbidity and mortality rates of Candida infections, especially among immunocompromised patients, are related to the increased resistance rate of these species and the limited therapeutic arsenal. In this context, we evaluated the anti-Candida potential and the cytotoxic profile of eugenol derivatives. Anti-Candida activity was evaluated on C. albicans and C. parapsilosis strains by minimum inhibitory concentration (MIC), scanning electron microscopy (SEM), and molecular docking calculations at the site of the enzyme lanosterol-14-α-demethylase active site, responsible for ergosterol formation. The cytotoxic profile was evaluated in HepG2 cells, in the presence and absence of the metabolizing system (S9 system). The results indicated compounds 1b and 1d as the most active ones. The compounds have anti-Candida activity against both strains with MIC ranging from 50 to 100 µg ml-1 . SEM analyses of 1b and 1d indicated changes in the envelope architecture of both C. albicans and C. parapsilosis like the ones of eugenol and fluconazole, respectively. Docking results of the evaluated compounds indicated a similar binding pattern of fluconazole and posaconazole at the lanosterol-14-α-demethylase binding site. In the presence of the S9 system, compound 1b showed the same cytotoxicity profile as fluconazole (1.08 times) and compound 1d had 1.23 times increase in cytotoxicity. Eugenol and other evaluated compounds showed a significant increase in cytotoxicity. Our results suggest compound 1b as a promising starting point candidate to be used in the design of new anti-Candida agent prototypes.


Asunto(s)
Candida , Fluconazol , Humanos , Candida/metabolismo , Fluconazol/farmacología , Antifúngicos/farmacología , Antifúngicos/química , Eugenol/farmacología , Simulación del Acoplamiento Molecular , Lanosterol , Candida albicans/metabolismo , Pruebas de Sensibilidad Microbiana , Esterol 14-Desmetilasa/metabolismo
11.
Mol Divers ; 26(6): 3365-3378, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34997872

RESUMEN

Related to a variety of gastrointestinal disorders ranging from gastric ulcer to gastric adenocarcinoma, the infection caused by the gram-negative bacteria Helicobacter pylori (H. pylori) poses as a great threat to human health; hence, the search for new treatments is a global priority. The H. pylori arginase (HPA) protein has been widely studied as one of the main virulence factors of this bacterium, being involved in the prevention of nitric oxide-mediated bacterial cell death, which is a central component of innate immunity. Given the growing need for the development of new drugs capable of combating the infection by H. pylori, the present work describes the search for new HPA inhibitors, using virtual screening techniques based on molecular docking followed by the evaluation of the proposed modes of interaction at the HPA active site. In vitro studies of minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC), followed by cytotoxicity activity in gastric adenocarcinoma and non-cancer cells, were performed. The results highlighted compounds 6, 11, and 13 as potential inhibitors of HPA; within these compounds, the results indicated 13 presented an improved activity toward H. pylori killing, with MIC and MBC both at 64 µg/mL. Moreover, compound 13 also presented a selectivity index of 8.3, thus being more selective for gastric adenocarcinoma cells compared to the commercial drug cisplatin. Overall, the present work demonstrates the search strategy based on in silico and in vitro techniques is able to support the rational design of new anti-H. pylori drugs.


Asunto(s)
Adenocarcinoma , Infecciones por Helicobacter , Helicobacter pylori , Humanos , Helicobacter pylori/fisiología , Infecciones por Helicobacter/tratamiento farmacológico , Infecciones por Helicobacter/microbiología , Arginasa/uso terapéutico , Simulación del Acoplamiento Molecular , Pruebas de Sensibilidad Microbiana , Antibacterianos/farmacología
12.
Antibiotics (Basel) ; 12(1)2022 Dec 28.
Artículo en Inglés | MEDLINE | ID: mdl-36671247

RESUMEN

Monteverdia ilicifolia is a Brazilian native plant, traditionally used to treat gastric diseases that are now associated with Helicobacter pylori and are commonly associated with several human diseases. We point out the M. ilicifolia extract as active against H. pylori. The crude extract produced with acetone:water presented the best H. pylori inhibitory activity of all five extracts (MIC 64 µg/mL). The ethyl-acetate fractions from crude extracts produced with ethanol and acetone showed a MIC of 64 µg/mL. Both ethyl-acetate fractions and the crude extract produced with acetone showed an antioxidant capacity of between 14.51 and 19.48 µg/mL in the DPPH assay. In the FRAP assay, two ethyl-acetate fractions (EAF2 and EAF4) presented the antioxidant capacity of 5.40 and 5.15 mM Trolox/g of extract. According to the results obtained from the antioxidant and antibacterial assays, two fractions (EAF2 and nBF5) were analyzed by mass spectrometry and confirmed the presence of monomeric, dimeric, trimeric tannins, and glycosylated flavonoids. Some compounds were tested using bioinformatics to evaluate the best enzyme inhibitors and the molecular interaction between the enzyme and the tested ligands. The presence of these polyphenol compounds could play an important role in antioxidant and inhibitory capacities against H. pylori and can be used to assist in the treatment or prevention of infection by H. pylori.

13.
Phytother Res ; 35(5): 2557-2567, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33350522

RESUMEN

Euphorbia umbellata is used for its anti-inflammatory properties; however, there are limited data available regarding its effects on vascular function. Its bark is rich in polyphenolic compounds, which potentially improve endothelial dysfunction (ED). This study proposes to investigate the effects of E. umbellata bark extracts and its polyphenolic compounds on arginase (ARG) activity and nitric oxide (NO)-related targets. Chromatographic procedures were used for the chemical characterisation of the extracts. Furthermore, in silico (molecular docking), in vitro (ARG inhibition), in vivo (streptozotocin-induced hyperglycemia model), and ex vivo (l-arginine metabolism, vascular reactivity, western blot, and biochemical) techniques were carried out. Quercetin, gallic acid, and ellagic acid were identified in the extracts. In silico screening predicted that gallic acid and quercetin would have the most promising interactions with ARG -identified cavities. This was confirmed in vitro as both compounds had a direct inhibitory effect on ARG, as was the case regarding the extracts. Oral treatment preserved endothelium-dependent vasodilation through ARG inhibition together with an increase in l-arginine bioavailability and endothelial NO synthase expression. Biochemical parameters determined the lack of toxicity for sub-chronic treatment. E. umbellata bark extracts and its compounds can contribute to ED treatment, at least partly, through the inhibition of vascular ARG.

14.
Life Sci ; 256: 117977, 2020 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-32603822

RESUMEN

AIMS: Silibinin is the major component of flavonolignans complex mixture (Silymarin), which is obtained from Silybum marianum (L.) Gaertn. Despite several reports about silibinin, little is known about its effects on gastric diseases. Then, the present study aims to evaluate the silibinin effect against Helicobacter pylori infection, gastric tumor cells and immunomodulation. MAIN METHODS: The anti-H. pylori effect was performed on 43504 and 43629 strains by minimum inhibitory concentration (MIC) determination, observing morphological alterations by scanning electron microscopy and in silico evaluation by molecular docking. Immunomodulatory activity (Interleukins-6 and 10, TNF-α and NO inhibition) was determined in H. pylori-stimulated macrophages and the cytotoxic activity on gastric adenocarcinoma cells prior and after metabolization by S9 fraction. KEY FINDINGS: Silibinin showed anti-H. pylori activity with MIC of 256 µg/mL, promoted important morphological changes in the bacterial cell wall, as blebs and clusters, suggesting interaction with Penicillin Binding Protein (PBP) subunits. Immunomodulatory potential was observed at 50 µg/mL with the inhibition of produced cytokines and NO by H. pylori-stimulated macrophages of 100% for TNF-ɑ, 56.83% for IL-6, and 70.29% for IL-10 and 73.33% for NO. Moreover, silibinin demonstrated significant cytotoxic activity on adenocarcinoma cells (CI50: 60.17 ± 0.95 µg/mL) with a higher selectivity index (SI: 1.52) compared to cisplatin. After metabolization silibinin showed an increase of cytotoxicity with a CI50 six-fold decrease (10.46 ± 0.25). SIGNIFICANCE: The use of silibinin may become an important alternative tool in the prevention and treatment of H. pylori infection and, consequently, in gastric cancer.


Asunto(s)
Antineoplásicos Fitogénicos/farmacología , Infecciones por Helicobacter/prevención & control , Helicobacter pylori/efectos de los fármacos , Simulación del Acoplamiento Molecular/métodos , Silibina/farmacología , Neoplasias Gástricas/prevención & control , Animales , Antineoplásicos Fitogénicos/uso terapéutico , Línea Celular Tumoral , Relación Dosis-Respuesta a Droga , Mucosa Gástrica/efectos de los fármacos , Mucosa Gástrica/microbiología , Mucosa Gástrica/patología , Infecciones por Helicobacter/patología , Helicobacter pylori/fisiología , Ratones , Pruebas de Sensibilidad Microbiana/métodos , Células RAW 264.7 , Silibina/química , Silibina/uso terapéutico , Neoplasias Gástricas/patología
15.
J Inorg Biochem ; 206: 111048, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-32151873

RESUMEN

Inflammation is a physiological process triggered in response to tissue damage, and involves events related to cell recruitment, cytokines release and reactive oxygen species (ROS) production. Failing to control the process duration lead to chronification and may be associated with the development of various pathologies, including autoimmune diseases and cancer. Considering the pharmacological potential of metal-based compounds, two new ruthenium complexes were synthesized: cis-[Ru(NO2)(bpy)2(5NIM)]PF6 (1) and cis-[RuCl(bpy)2(MTZ)]PF6 (2), where bpy = 2,2'-bipyridine, 5NIM = 5-nitroimidazole and MTZ = metronidazole. Both products were characterized by spectroscopic techniques, followed by Density Functional Theory (DFT) calculations in order to support experimental findings. Afterwards, their in vitro cytotoxic, antioxidant and anti-inflammatory activities were investigated. Compounds 1 and 2 presented expressive in vitro antioxidant activity, reducing lipid peroxidation and decreasing intracellular ROS levels with comparable effectiveness to the standard steroidal drug dexamethasone or α-tocopherol. These complexes showed no noticeable cytotoxicity on the tested cancer cell lines. Bactericidal assay against metronidazole-resistant Helicobacter pylori, a microorganism able to disrupt oxidative balance, unraveled compound 1 moderate activity over that strain. Besides this, it was able to inhibit interleukin-6 (IL-6) and tumor necrosis factor-α (TNF- α) production as well as interleukin-1ß (IL-1ß) and cyclooxygenase-2 (COX-2) expression in lipopolysaccharide (LPS)-stimulated RAW264.7 macrophages. This latter activity is remarkable, which has not been reported for other ruthenium-based complexes. Altogether, these results suggest cis-[Ru(NO2)(bpy)2(5NIM)]PF6 complex has potential pharmacological application as an anti-inflammatory agent that deserve further biological investigation.


Asunto(s)
Antibacterianos/farmacología , Antiinflamatorios/farmacología , Antineoplásicos/farmacología , Antioxidantes/farmacología , Complejos de Coordinación/farmacología , Imidazoles/química , Rutenio/química , Células A549 , Animales , Antibacterianos/química , Antiinflamatorios/química , Antineoplásicos/química , Antioxidantes/química , Bacterias/efectos de los fármacos , Proliferación Celular , Complejos de Coordinación/química , Humanos , Peroxidación de Lípido , Células MCF-7 , Ratones , Estructura Molecular , Células RAW 264.7 , Superóxidos/metabolismo
16.
Nat Prod Res ; 34(16): 2332-2335, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-30600691

RESUMEN

Paullinia cupana Kunth, commonly known as guarana, is a native Brazilian plant species from the Amazon area that presents various biological effects, including antimicrobial action. The aim of this study was to chemically analyse the semipurified aqueous extract (AqF) of the plant and to evaluate the activity of crude (CE), ethyl-acetate (EAF), and AqF extracts against Helicobacter pylori. The chemical profile of AqF was determined based on solid analysis 13C-NMR, direct infusion mass spectrometry (ESI-MS), and MALDI-TOF. The 13C-NMR spectrum showed characteristics of flavan-3-ol and oligomeric proanthocyanidins. ESI-MS revealed the presence of procyanidin, caffeic acid and its derivatives. MALDI-TOF analysis detected procyanidins of up to 6 units and profisetinidins of up to 5 units. Whereas CE and EAF showed inhibitory activity against H. pylori, CE, EAF, and AqF presented not high inhibitory activity against urease. The results demonstrate the potential of P. cupana to control and prevent H. pylori infection.


Asunto(s)
Helicobacter pylori/efectos de los fármacos , Paullinia/química , Extractos Vegetales/química , Antioxidantes/farmacología , Brasil , Cromatografía de Gases y Espectrometría de Masas , Infecciones por Helicobacter/prevención & control , Extractos Vegetales/farmacología , Proantocianidinas/farmacología , Ureasa/antagonistas & inhibidores
17.
Curr Med Chem ; 27(23): 3967-3982, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-30827224

RESUMEN

Expressed by a variety of plants, fungi and bacteria, the urease enzyme is directly associated with the virulence factor of many bacteria, including Helicobacter pylori, a gram-negative bacterium related to several gastrointestinal diseases and responsible for one of the most frequent bacterial infections throughout the world. The Helicobacter pylori Urease (HPU) is a nickel-dependent metalloenzyme expressed in response to the environmental stress caused by the acidic pH of the stomach. The enzyme promotes the increase of gastric pH through acid neutralization by the products of urea hydrolysis, then critically contributing to the colonization and pathogenesis of the microorganism. At the same time, standard treatments for Helicobacter pylori infections have limitations such as the increasing bacterial resistance to the antibiotics used in the clinical practice. As a strategy for the development of novel treatments, urease inhibitors have proved to be promising, with a wide range of chemical compounds, including natural, synthetic and semisynthetic products to be researched and potentially developed as new drugs. In this context, this review highlights the advances in the field of HPU inhibition, presenting and discussing the basis for the research of new molecules aiming at the identification of more efficient therapeutic entities.


Asunto(s)
Enfermedades Gastrointestinales , Infecciones por Helicobacter , Helicobacter pylori , Antibacterianos , Inhibidores Enzimáticos , Humanos , Ureasa
18.
Curr Top Med Chem ; 19(30): 2795-2804, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31721712

RESUMEN

BACKGROUND: Helicobacter pylori is a gram-negative bacterium related to chronic gastritis, peptic ulcer and gastric carcinoma. During its infection process, promotes excessive inflammatory response, increasing the release of reactive species and inducing the production of pro-inflammatory mediators. Inducible Nitric Oxide Synthase (iNOS) plays a crucial role in the gastric carcinogenesis process and a key mediator of inflammation and host defense systems, which is expressed in macrophages induced by inflammatory stimuli. In chronic diseases such as Helicobacter pylori infections, the overproduction of NO due to the prolonged induction of iNOS is of major concern. OBJECTIVES: In this sense, the search for potential iNOS inhibitors is a valuable strategy in the overall process of Helicobacter pylori pathogeny. METHODS: In silico techniques were applied in the search of interesting compounds against Inducible Nitric Oxide Synthase enzyme in a chemical space of natural products and derivatives from the Analyticon Discovery databases. RESULTS: The five compounds with the best iNOS inhibition profile were selected for activity and toxicity predictions. Compound 9 (CAS 88198-99-6) displayed significant potential for iNOS inhibition, forming hydrogen bonds with residues from the active site and an ionic interaction with heme. This compound also displayed good bioavailability and absence of toxicity/or from its probable metabolites. CONCLUSION: The top-ranked compounds from the virtual screening workflow show promising results regarding the iNOS inhibition profile. The results evidenced the importance of the ionic bonding during docking selection, playing a crucial role in binding and positioning during ligand-target selection for iNOS.


Asunto(s)
Antibacterianos/uso terapéutico , Inhibidores Enzimáticos/uso terapéutico , Infecciones por Helicobacter/tratamiento farmacológico , Helicobacter pylori/aislamiento & purificación , Óxido Nítrico Sintasa de Tipo II/antagonistas & inhibidores , Antibacterianos/farmacocinética , Antibacterianos/farmacología , Antibacterianos/toxicidad , Inhibidores Enzimáticos/farmacocinética , Inhibidores Enzimáticos/farmacología , Inhibidores Enzimáticos/toxicidad , Infecciones por Helicobacter/microbiología , Humanos
19.
J Ethnopharmacol ; 237: 255-265, 2019 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-30928500

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: Euphorbia tirucalli L. is widely used by Brazilian folk medicine, mainly for its anticancer activity. However, its commercialization was banned by The Brazilian National Sanitary Surveillance Agency (ANVISA) due to the presence of some compounds considered toxic, such as the diterpene esters. AIM OF THE STUDY: Chemical and biological analyses were performed with the Brazilian Euphorbia tirucalli latex to support its wide traditional use in Brazil. MATERIAL AND METHODS: Latex was collected by using two procedures, in a solution of dichloromethane: methanol (3:1, 100 mL) and in 100 mL of distilled water. The first procedure was concentrated as a crude extract and the second one was partitioned with hexane and dichloromethane. The partitions and crude extract were subjected to phytochemical analyses using three different methods: Fourier transform-ion cyclotron resonance mass spectrometry (FT-ICR MS) with electrospray ionization sources in negative mode (ESI(-)) as well as in tandem mass spectrometry ESI(-) MS/MS and Atmospheric Pressure Chemical Ionization in positive mode (APCI(+)), Gas Chromatography coupled Mass Spectrometry (GC-MS) and Nuclear Magnetic Resonance (NMR) (1H-NMR and 13C-NMR). The cytotoxic potential was evaluated using the crude extract in macrophages RAW 264.7 and Gastric Adenocarcinoma (AGS) cancer cells. The evaluation of immunomodulatory activity was made through the detection of Nitric Oxide (NO) and cytokines as Tumor necrosis factor α (TNF-α) and Interleukin-6 (IL-6). RESULTS: GC-MS showed the presence of some esters of fatty acids, for instance myristic, palmitic, stearic, oleic and linoleic acid and, mainly, triterpenes such as euphol and tirucallol. With NMR, most of the signals were related to triterpenoids euphol and tirucallol. However, when the latex was analyzed with ESI(-) FT-ICR MS, a wide variety of molecules from different classes of natural products (fatty acids, diterpenes, triterpenes, steroids) were found. On the other hand, when APCI(+)FT-ICR MS was used, the ion M+. At ratio mass-charge (m/z) 426.38567, related to triterpenes euphol and tirucallol masses, presented the most intense peak, with a mass error of -0.11, indicating high accuracy. Diterpene esters from 4-deoxyphorbol and ingenol were identified only by ESI(-)FT-ICR MS and ESI(-)FT-ICR MS/MS. When evaluated biologically, the crude latex showed immunomodulatory activity, as it reduced the production of the pro-inflammatory cytokines TNF-α, IL-6 and NO, and the effect on NO reduction was more significant, obtaining in a similar result to the N(ω)-Nitro-L-Arginine Methyl Ester (L-NAME) standards, as well as significant cytotoxic activity with half inhibitory concentration (IC50) values of 69.43 ±â€¯1.29 µg/mL against AGS without damaging healthy ones. CONCLUSION: It was verified that the Brazilian Euphorbia tirucalli latex consists mainly of the triterpenes euphol and tirucallol, which may be the main cause of the anticancer activity attributed to the plant, but many other minor compounds could have been determined by the FT-ICR MS method, such as the diterpene esters. It has antitumor potential because it acts selectively against cancer cells and it also prevents the progression of tumors, because it carries an important immunomodulatory effect.


Asunto(s)
Antineoplásicos/análisis , Antineoplásicos/farmacología , Euphorbia , Látex/química , Látex/farmacología , Fitoquímicos/análisis , Fitoquímicos/farmacología , Animales , Brasil , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Cromatografía de Gases y Espectrometría de Masas , Humanos , Medicina Tradicional , Ratones , Células RAW 264.7 , Espectrometría de Masas en Tándem , Triterpenos/análisis , Triterpenos/farmacología
20.
Food Res Int ; 119: 751-760, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-30884712

RESUMEN

The long-term use of anti-inflammatory drugs is the most common cause of gastric ulcer disease, one of the major gastrointestinal disorders affecting people worldwide. Persea americana Mill. (avocado) seed is a by-product generally discarded as waste, but can be used to treat gastric disorder due to its anti-inflammatory, antioxidant and antimicrobial activities. The aim of the present study was to evaluate the potential protective effects of the ethyl acetate fraction of avocado seeds (SEAP) extracts against indomethacin-induced gastric ulcer in mice. It was found that SEAP were effective in mitigating oxidative stress through a decrease on the oxidized products levels (reduction of 90% in lipid peroxidation in plasma) and increasing superoxide dismutase enzyme (SOD) activity (4.25-fold increase compared to the indomethacin group), also preventing the rise in ulcer and lesions areas (92% of protection) and histological changes induced by indomethacin. Chemical analysis using mass spectrometry by (-)-ESI-FT-ICR MS revealed the presence of (-)-epicatechin and (+)-catechin, confirmed by HPLC-DAD, and other important phenolic compounds in avocado seeds, such as caffeoylquinic acid, flavonoids, phenylpropanoids and tannins, substances that promote inhibition of pathways involved in gastric ulcer formation. Thus, avocado seeds extract may be a suitable natural source for the prevention and treatment of gastric ulcer.


Asunto(s)
Indometacina/efectos adversos , Persea/química , Extractos Vegetales/uso terapéutico , Semillas/química , Úlcera Gástrica/prevención & control , Animales , Antioxidantes/análisis , Brasil , Catequina/análisis , Cromatografía Líquida de Alta Presión , Modelos Animales de Enfermedad , Flavonoides/análisis , Peroxidación de Lípido , Masculino , Ratones , Oxidación-Reducción , Fenoles/análisis , Extractos Vegetales/química , Úlcera Gástrica/patología , Superóxido Dismutasa/sangre , Superóxido Dismutasa/metabolismo
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